Superhydrophobic straw felt for oil absorption

Abstract

Water pollution caused by oil spills, industrial and household wastewater seriously endangers environments and ecosystems. Commercially available oil absorption felts have been widely used in oil removal; however, their relatively poor absorption capacity and high cost restrict practical applications. Therefore, it is of great significance to develop a new oil-removing material with excellent oil absorption capacity and low cost. Here, a new kind of oil absorption felt originated from waste straw fibers is proposed. Waste rice straw fibers are formed into felts with special shapes by molds and further transferred into superhydrophobicity and superoleophilicity by a simple chemical treatment process. The superhydrophobic straw felts possess excellent absorption capacity for different oils with >95% oil/water separation efficiency. Weight of absorbed oil of the superhydrophobic straw felts is up to 2.55 times as much as that of commercially available oil absorption felts. More interestingly, the superhydrophobic straw felts are applicable to harsh conditions including strong turbulence, strongly acidic water, and intensive ultraviolet irradiation. Using waste rice straw fibers as raw materials, the superhydrophobic straw felts may have promising application prospect in the treatment of oil spills, industrial and household waste water.